Uranium Mining In Arizona
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Uranium mining in Arizona has taken place since 1918. Prior to the uranium boom of the late 1940s, uranium in
Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
was a byproduct of
vanadium Vanadium is a chemical element; it has Symbol (chemistry), symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an ...
mining of the mineral
carnotite Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula K2( U O2)2( VO4)2·3 H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present. Occurrence Carnotite ...
.


Carrizo Mountains

Uranium mining started in 1918 in the
Carrizo Mountains The Carrizo Mountains (36°50' N, 109°7'W) is a small, mostly circular mountain range 15 to 20 km (9 to 12 miles) in diameter located on the Colorado Plateau in northeastern Arizona. The range is about southwest of the Four Corners. The hig ...
as a byproduct of
vanadium Vanadium is a chemical element; it has Symbol (chemistry), symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an ...
mining. The district is in
Apache County Apache County is a county in the northeast corner of the U.S. state of Arizona. Shaped in a long rectangle running north to south, as of the 2020 census, its population was 66,021. The county seat is St. Johns. Most of the county is occupie ...
, in the northeast corner of Arizona. The
uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
and
vanadium Vanadium is a chemical element; it has Symbol (chemistry), symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an ...
occur as
carnotite Carnotite is a potassium uranium vanadate radioactive mineral with chemical formula K2( U O2)2( VO4)2·3 H2O. The water content can vary and small amounts of calcium, barium, magnesium, iron, and sodium are often present. Occurrence Carnotite ...
in sandstone of the Salt Wash member of the
Morrison Formation The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltston ...
(
Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...
). Production stopped in 1921. Another period of mining took place from 1941 to 1966, producing 360,000 pounds (160 metric tons) of uranium oxide (U3O8).


Monument Valley

A
Navajo The Navajo or Diné are an Indigenous people of the Southwestern United States. Their traditional language is Diné bizaad, a Southern Athabascan language. The states with the largest Diné populations are Arizona (140,263) and New Mexico (1 ...
discovered uranium in 1942 in
Monument Valley Monument Valley (, , meaning "valley of the rocks") is a region of the Colorado Plateau characterized by a cluster of sandstone buttes, with the largest reaching above the valley floor. The most famous butte formations are located in northeas ...
on the
Navajo Nation The Navajo Nation (), also known as Navajoland, is an Indian reservation of Navajo people in the United States. It occupies portions of northeastern Arizona, northwestern New Mexico, and southeastern Utah. The seat of government is located in ...
in northeast
Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
. The first mine in the district opened in 1948. Uranium and uranium-vanadium minerals occur in fluvial channels of the Shinarump Sandstone member of the
Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...
Chinle Formation The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In ...
. Ore deposits are associated with carbonized wood in the sandstone. Mining stopped in the
Monument Valley Monument Valley (, , meaning "valley of the rocks") is a region of the Colorado Plateau characterized by a cluster of sandstone buttes, with the largest reaching above the valley floor. The most famous butte formations are located in northeas ...
district in 1969, after producing 8.7 million pounds (3900 metric tons) of uranium oxide, more than has been produced from any other uranium mining district in Arizona. In 2005 the
Navajo Nation The Navajo Nation (), also known as Navajoland, is an Indian reservation of Navajo people in the United States. It occupies portions of northeastern Arizona, northwestern New Mexico, and southeastern Utah. The seat of government is located in ...
declared a moratorium on uranium mining on the reservation, for environmental and health reasons.


Lukachukai Mountains

In 1948, a
copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...
deposit in the
Moenkopi Formation The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a Geological unit, group ...
was discovered to have economic concentrations of
uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
. The deposit was in the Lukachukai Mountains of
Apache County Apache County is a county in the northeast corner of the U.S. state of Arizona. Shaped in a long rectangle running north to south, as of the 2020 census, its population was 66,021. The county seat is St. Johns. Most of the county is occupie ...
. Uranium totaling 3.5 million pounds (1600 metric tons) of U3O8 was produced from 1950 until the mines closed in 1968.


Cameron district

Navajo The Navajo or Diné are an Indigenous people of the Southwestern United States. Their traditional language is Diné bizaad, a Southern Athabascan language. The states with the largest Diné populations are Arizona (140,263) and New Mexico (1 ...
prospector Hosteen Nez found uranium near
Cameron Cameron may refer to: People * Clan Cameron, a Scottish clan * Cameron (given name), a given name (including a list of people with the name) * Cameron (surname), a surname (including a list of people with the name) ;Mononym * Cam'ron (born 19 ...
in
Coconino County Coconino County is a County (United States), county in the North Central Arizona, North-Central part of the U.S. state of Arizona. Its population was 145,101 at the 2020 United States census, 2020 census. The county seat is Flagstaff, Arizon ...
in 1950. The uranium is in the
Kayenta Formation The Kayenta Formation is a geological formation in the Glen Canyon Group that is spread across the Colorado Plateau area of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah. Originally suggested as being Sinemur ...
and the
Chinle Formation The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In ...
. Production was from 1950 to 1963, and totaled 1.2 million pounds (540 metric tons) of U3O8.


Collapse breccia pipes

Uranium was discovered in the Orphan copper mine near the south rim of the
Grand Canyon The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon Nati ...
in 1950. The mine has been private property since 1906, and is today completely surrounded by
Grand Canyon National Park Grand Canyon National Park is a List of national parks of the United States, national park of the United States located in northwestern Arizona, the 15th site to have been named as a national park. The park's central feature is the Grand Canyo ...
. The discovery led to the finding of uranium in other collapse breccia pipes in northern Arizona. The breccia pipes were formed when overlying rocks collapsed into caverns formed in the
Mississippian Mississippian may refer to: * Mississippian (geology), a subperiod of the Carboniferous period in the geologic timescale, roughly 360 to 325 million years ago * Mississippian cultures, a network of precontact cultures across the midwest and Easte ...
Redwall Limestone The Redwall Limestone is an erosion-resistant, Mississippian age, cliff-former, cliff-forming geological formation that forms prominent, red-stained cliffs in the Grand Canyon. these cliffs range in height from to . It is one of the most fossili ...
. The pipes are typically in diameter, and may extend up to vertically.


Sierra Ancha district

Uranium mining started in 1953 from deposits in the
Precambrian The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of t ...
Dripping Spring Quartzite in
Gila County Gila County ( ) is a county in the central part of the U.S. state of Arizona. As of the 2020 census, the population was 53,272. The county seat is Globe. Gila County comprises the Payson, Arizona micropolitan statistical area which is incl ...
. The uranium mineral is most commonly
uraninite Uraninite, also known as pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium c ...
, which occurs with
pyrite The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue ...
,
marcasite The mineral marcasite, sometimes called "white iron pyrite", is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both ...
, and
chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a Mohs scale, hardness of 3.5 to 4 ...
. The orebodies are in veins or strataform deposits within one-half mile of
diabase Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-gra ...
intrusions.


Date Creek Basin

The Anderson uranium deposit was discovered in 1955 by an airborne gamma-radiation survey. Small amounts of ore were produced from 1955 to 1959. Uranium is associated with organic material in carbonaceous
Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
siltstones and mudstones of
lacustrine A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...
and
paludal Paludal is derived from the Latin language, Latin word ''palus'' ("marsh"). *Paludal, in geology, refers to sediments that accumulated in a marsh environment. *Paludal, in ecology, refers to the environment of a marsh. Sedimentology {{Geology-s ...
origin of the Chapin Wash formation of the Date Creek Basin in
Yavapai The Yavapai ( ) are a Native American tribe in Arizona. Their Yavapai language belongs to the Upland Yuman branch of the proposed Hokan language family. Today Yavapai people are enrolled in the following federally recognized tribes: * Fort ...
,
La Paz La Paz, officially Nuestra Señora de La Paz (Aymara language, Aymara: Chuqi Yapu ), is the seat of government of the Bolivia, Plurinational State of Bolivia. With 755,732 residents as of 2024, La Paz is the List of Bolivian cities by populati ...
, and
Mohave Mojave or Mohave most often refers to: *Mojave Desert *Mojave River *Mohave people *Mojave language *Mohave County, Arizona, a county in the U.S. state of Arizona Mojave or Mohave may also refer to: Places * Fort Mojave Indian Reservation * Mo ...
counties. The Anderson mine is now owned by Concentric Energy Corp. which is doing extensive development work to bring it into production.


Porphyry copper byproduct

For some years starting in 1980, the Twin Buttes copper mine in
Pima County Pima County ( ) is a County (United States), county in the south central region of the U.S. state of Arizona, one of 15 List of counties in Arizona, counties in the state. As of the 2020 United States census, 2020 census, the population was 1 ...
recovered uranium as a byproduct from leach solutions recovering copper from waste material.


Uranium mining and native people

After the end of World War II, the United States encouraged
uranium mining Uranium mining is the process of extraction of uranium ore from the earth. Over 50,000 tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of w ...
to build nuclear weapons stockpiles. Large
uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
deposits were found on and near the
Navajo Reservation The Navajo Nation (), also known as Navajoland, is an Indian reservation of Navajo people in the United States. It occupies portions of northeastern Arizona, northwestern New Mexico, and southeastern Utah. The seat of government is located in ...
, and mining companies hired many Navajos. Disregarding the health risks of radiation exposure, the private companies and the
United States Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by the U.S. Congress to foster and control the peacetime development of atomic science and technology. President Harry ...
failed to inform the Navajo workers about the dangers and to regulate the mining to minimize contamination. As more data was collected, they were slow to take appropriate action for the workers. Studies show that the Navajo mine workers and numerous families on the reservation have suffered high rates of disease from environmental contamination, but for decades, industry and the government failed to regulate or improve conditions, or inform workers of the dangers. As high rates of illness began to occur, workers were often unsuccessful in court cases seeking compensation, and the states at first did not officially recognize
radon Radon is a chemical element; it has symbol Rn and atomic number 86. It is a radioactive noble gas and is colorless and odorless. Of the three naturally occurring radon isotopes, only Rn has a sufficiently long half-life (3.825 days) for it to b ...
illness. In 1990 the US Congress passed the
Radiation Exposure Compensation Act The United States Radiation Exposure Compensation Act (RECA) is a federal statute implemented in 1990, set to expire in July 2024, providing for the monetary compensation of people, including atomic veterans, who contracted cancer and a number ...
, to settle such cases and provide needed compensation. In 2008 the US Congress authorized a five-year, multi-agency cleanup of uranium contamination on the Navajo Nation reservation; identification and treatment of contaminated water and structures has been the first priority. Certain water sources have been closed, and numerous contaminated buildings have been taken down. By the summer of 2011, EPA had nearly completed the first major project of removal of 20,000 cubic yards of contaminated earth from the Skyline Mine area. There is a current producing uranium mine in the
Whetstone Mountains The Whetstone Mountains are a range of mountains in Cochise County, Arizona, Cochise County, southeastern Arizona. The Opata people, Opata called the mountains ''Babocomari'', a name still attached to the nearby Babocomari River. The Spanish co ...
of
Cochise County Cochise County ( ) is a county in the southeastern corner of the U.S. state of Arizona. It is named after Cochise, a Chiricahua Apache who was a key war leader during the Apache Wars. The population was 125,447 at the 2020 census. The county ...
. The mine has restarted and has been in operation for five years. The government has also closed down about around the mountain which is all was public lands.


Current activity

There are currently no producing uranium mines in
Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
.
Denison Mines Denison Mines Corp. is a Canadian uranium exploration, development, and production company. Founded by Stephen B. Roman, and best known for its uranium mining in Blind River and Elliot Lake, it later diversified into coal, potash, and other pro ...
planned to begin mining its Arizona One mine in 2007. The deposit is in a
breccia pipe A breccia pipe, also referred to as a chimney, is a mass of breccia (rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix), often in an irregular and cylindrical shape. Characteristics When exposed a ...
on the
Colorado Plateau The Colorado Plateau is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the Southwestern United States. This plateau covers an area of 336,700 km2 (130,000 mi2) within w ...
of northern Arizona. In March 2011, the State of Arizona issued air and water permits to Denison which would allow uranium mining to resume at three locations north of the Grand Canyon, subject to federal approval. As of May 2015, Energy Fuels was preparing to mine uranium at its Canyon mine, a deposit on US Forest Service land, six miles from the south rim of the Grand Canyon. The deposit was discovered in the 1970s, and partially developed as an underground mine under a Forest Service permit in the late 1980s, but never put into production. The Canyon deposit holds enough ore to yield an estimated 1.63 million pounds of uranium concentrate U3O8. A coalition of groups, including the
Havasupai The Havasupai people (Havasupai: ''Havsuw' Baaja'') are a Native American people and tribe who have lived in the Grand Canyon for at least the past 800 years. Their name means "people of the blue-green water", referring to Havasu Creek, a t ...
Tribe, the
Sierra Club The Sierra Club is an American environmental organization with chapters in all 50 U.S. states, Washington, D.C., Washington D.C., and Puerto Rico. The club was founded in 1892, in San Francisco, by preservationist John Muir. A product of the Pro ...
, th
Grand Canyon Trust
and the
Center for Biological Diversity The Center for Biological Diversity is a nonprofit membership organization known for its work protecting endangered species through legal action, scientific petitions, creative media and grassroots activism. It was founded in 1989 by Kieran Suck ...
, sued the Forest Service to stop the reactivation of the mine. In April 2015 the US District Court for the District of Arizona ruled in favor of the Forest Service and Energy Fuels, and allowed work on the mine to proceed. The plaintiffs plan to appeal. Energy Fuels has also been developing its Pine Nut mine located north of the Grand Canyon since 1986.


Ban on uranium mining near Grand Canyon National Park

In July 2009 Secretary of the Interior
Ken Salazar Kenneth Lee Salazar (born March 2, 1955) is an American lawyer, politician, and diplomat who served as United States ambassador to Mexico from 2021 to 2025. He previously served as the 50th United States Secretary of the Interior in the administ ...
announced a two-year ban on new mining on federal land in an area of approximately surrounding
Grand Canyon National Park Grand Canyon National Park is a List of national parks of the United States, national park of the United States located in northwestern Arizona, the 15th site to have been named as a national park. The park's central feature is the Grand Canyo ...
. Although the ban is on all mining, the main effect is on exploration and development of breccia-pipe uranium deposits. Those claims on which commercial mineral deposits have already been discovered are exempt from the ban. During the two-year ban the Department of the Interior will study a proposed 20-year ban on new mining in the area."Two-year ban on mining near Grand Canyon imposed," ''Mining Engineering'', September 2009, p. 7. In January 2012, secretary
Ken Salazar Kenneth Lee Salazar (born March 2, 1955) is an American lawyer, politician, and diplomat who served as United States ambassador to Mexico from 2021 to 2025. He previously served as the 50th United States Secretary of the Interior in the administ ...
approved a 20-year ban on mining around the
Grand Canyon The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon Nati ...
. This decision preserves about “1 million acres near the Grand Canyon, an area known to be rich in high-grade uranium ore reserves” and has generated a number of different responses The ban is supported by the president of the League of Conservation voters, Gene Karpinski: "Extending the current moratorium on new uranium mining claims will protect drinking water for millions downstream.” Many environmental groups agree that such mining would endanger the Colorado River as a source of water not only for wildlife, but for tens of millions of people; Phoenix, Las Vegas and Los Angeles rely on the river for drinking water. With areas of contamination already noted in United States environmental impact reports on old mining operations, opposition fears that allowing mining to expand and continue would increase the levels of contamination in the river. Supporters of the mining around the Grand Canyon argue that large-scale contamination from accidents involving mining are unlikely. According to an Arizona Geological survey, “60 metric tons of dissolved uranium is naturally carried by the Colorado River through the Grand Canyon in an average year". J.E. Spencer, AZGS Senior Geologist, argues that in one hypothetical, worst-case scenario experiment, a truck carrying “thirty metric tons (66,000 pounds) of one-percent uranium ore” spilling and washing into the Colorado River increases the natural uranium level in the river by an insignificant amount. Providing further data on uranium levels in the Colorado River, a 2010 United States Geological survey found that the river carries about 40 to 80 tons through the canyon each year. In 2011 more than 200 Arizona small businesses addressed postcards to Interior Secretary Ken Salazar sign the 20-year ban on new uranium mining near the Grand Canyon, to preserve thousands of tourism-related jobs. President of the League of Conservation voters Gene Karpinski agreed that protecting the tourism industry, which relies on the Grand Canyon, is more economically important than mining near the canyon. Coconino County Supervisor Carl Taylor argued that Uranium mining poses a great threat to tourism in the canyon and surrounding areas. Some believe that one mining accident could be destructive for tourism in the highly popular park. Interior Secretary Ken Salazar states that “the Grand Canyon attracts more than 4 million visitors a year and generates an estimated $3.5 billion in economic activity”. Salazar also stated that people from the United States and even all over the world come to visit and see the Grand Canyon. He believes that allowing mining in this area to be pursued would negatively impact this tourism industry. Some argue that not allowing the mining to occur destroys years of resource development. Hal Quinn, president and CEO of the National Mining Association states that banning mining in the Grand Canyon only deprives the United States of energy and minerals that are critical to the survival and strength of the US economy. The mining industry agrees, believing that a ban on mining around the Grand Canyon would negatively impact Arizona's local economy and the United States’ energy independence. Jonathan DuHamel states that a permanent ban on mining would eliminate hundreds of potential jobs. Former presidential candidate John McCain argues that opposition to the mining provoked by environmental groups who have the goal of killing mining and grazing jobs throughout Arizona. The increasing number of claims that began in 2006 was a direct result of the rising uranium prices that began that year. Higher uranium prices encouraged mining companies to locate and mine new deposits around the canyon area. In 2011, when the price of uranium lowered about 35%, companies continued to explore the area.


See also

*
Arizona breccia pipe uranium mineralization During the late 1970s and through the 1980s, Mohave and Coconino County, Arizona, immediately north and south of the Grand Canyon and west of the Navajo Indian Reservation were explored for Arizona breccia pipe uranium mineralization. The search ar ...
*
Uranium mining in the United States Uranium mining in the United States produced of U3O8 in 2023, 15% of the 2018 production of of U3O8. The 2023 production represents 0.4% of the uranium fuel requirements of the US's nuclear power reactors for the year. Production came from f ...
*
Uranium mining in Utah Uranium mining in Utah, a state of the United States, has a history going back more than 100 years. Uranium mining started as a byproduct of vanadium mining about 1900, became a byproduct of radium mining about 1910, then back to a byproduct of v ...
*
Uranium mining in Colorado Uranium mining in Colorado, United States, goes back to 1872, when pitchblende ore was taken from gold mines near Central City, Colorado. The Colorado uranium industry has seen booms and busts, but continues to this day. Not counting byproduct ...
*''
The Navajo People and Uranium Mining ''The Navajo People and Uranium Mining'' (2006) is a non-fiction book edited by Doug Brugge, Timothy Benally, and Esther Yazzie-Lewis; it uses oral histories to tell the stories of Navajo Nation families and miners in the uranium mining industry ...
''


References

{{DEFAULTSORT:Uranium Mining In Arizona Mining in Arizona
Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...